Ever wonder why we have so many words with multiple meanings? Consider the word “mean,” which can convey hurtful behavior (as in “mean girls”), signify a mathematical middle or indicate intent — as in, what does this word mean?

This verbal mystery has probably not kept you up at night. But linguists have devoted significant brain cells to figuring out why there are so many words that mean more than one thing. Why develop a language, whose main goal should be to promote clear communication, in which confusion is inevitable? Why not just designate one meaning for each word and be done? In fact, multiple meanings seem so contrary to the building of an efficient language that some experts have even argued that perhaps language’s true purpose wasn’t to communicate at all, as we’ve always assumed.

It turns out there’s a method to the language madness; the way we talk is efficient after all. Yes, many of our words have multiple meanings, but for the most part, we aren’t confused by them. That’s because the other important element of language is context.

Researchers at Massachusetts Institute of Technology (MIT) write in the journal Cognition that assigning more than one meaning to a word is a way to shortcut communication and make it less tedious. After analyzing words with multiple meanings in three languages — English, German and Dutch — the scientists found that they all shared some important traits. They were all short and they all had simple sound patterns that were simple to pronounce and easily recognizable to listeners.

The more of these words included in a language, the faster, and more efficiently, people could understand one another — as long as they were also good at parsing out which of the words’ different meanings were appropriate. And for that, says lead author Steven Piantadosi, a postdoctoral researcher now at the University of Rochester, speakers use context cues, such as where they are, their environment and the subject under discussion.

So, if you and a friend are sitting in a baseball stadium, for instance, and you want to comment on the game, you don’t have to specify that the version of “run” you’re using is the verb and not the noun that refers to a tear in stockings. Other contextual cues make that clear to the listener. That makes our language efficient, rather than tedious and incomprehensible.

“When you’re talking to somebody, and you are in the same situation, looking at the same thing or talking about the same topic, then you have all this shared information,” says Piantadosi. “So the most efficient communication won’t specify all that. It’s assumed.”